The applicant's own Norwegian patent application nos. 19994244, 20015048, 20016216, 20020619 and 20023919 describe prior art pipe separators for the separation of oil, water and/or gas downhole, on the sea bed or on the surface, on a platform or similar, in which various system solutions are used, comprising combinations and pipe separators and other separation equipment, that have contributed to a significant development of separation technology, in particular for the separation of oil and water.
During tests, among other things in connection with the development of the above patented solutions, it emerged, however, as will be explained in further detail later, that it is possible to improve oil/water separation in certain situations by adding water to the oil/water fluid prior to separation. Moreover, it emerged that, by subjecting the fluid to shear forces prior to separation, faster phase inversion can be achieved, i.e. a faster transition from the initial fluid, consisting of a mixture of water dispersed in an oil phase, to separate layers of water and oil.